Waterway Management - Lower Vasse River and Toby Inlet

The City of Busselton has completed a trial pit of approximately 4 tons of sediment removal on a section of the lower Vasse River. The purpose of the trial was to see how the material reacts when excavated/handled and will also undergo various tests including ASS (Acid Sulphate Soils) and water content. As this was a trial, there were no requirements to get any specific additional approvals. The material will be transported to the City’s transfer facility and will be further inspected and treated for ASS.

The City of Busselton continues to work through its 6 staged-approach of sediment removal, established in 2022, with locations for each stage chosen based on water quality and priority.

The completion of the Stage 2 sediment removal in June 2023 saw approximately 670t of dry sediment removed. This sediment was laid to semi-dry in collection bags before being laid out on an Acid Sulphate Soils (AA) treatment pad at the Busselton Waste Transfer Station to treat and neutralise it. The City was then able to repurpose the sediment as daily cover at the Dunsborough Waste Facility. The Department of Water and Environment Regulation (DWER) continue to monitor the water in the river to ensure effectiveness of the current sediment removal program. It was found during Stages 1 and 2 that pH levels and the clarity of the water were kept within acceptable ranges throughout the works. This data assists City and DWER officers with ongoing evaluation of the program.

In April 2024 the City advertised a tender for Stage 3 of the sediment removal process and this tender will close on 8 May. Stage 3 will focus on the part of the river near Strelly Street to upstream of the river bend. The total budget for Stage 3 is $938,025, with $407,964 funded by the State NRM Community Stewardship Program.

Stage 3 of sediment removal will occur along Strelly Street to upstream of the river bend.

In addition to sediment removal works, DWER have conducted a large-scale application of a phosphorus-binding clay (Phoslock) from the Causeway bridge downstream to the pedestrian bridge. The results from this, plus the results from Stage 2 of sediment removal, will be presented to Council by DWER in June 2024.

The City of Busselton has also collaborated with DWER to develop a Water Treatment Assessment Framework ensuring decision-making on the management of the waterways (Lower Vasse River and Toby Inlet) is scientifically robust and evidence-based.

Work continues on waterway management and further updates will be provided when available.

Waterway Management and Sustainability Open Day

In collaboration with the Department of Water and Environmental Regulation, Geocatch and the Toby Inlet Catchment Group the City will be hosting an open day to showcase some of the waterway, environmental and sustainability management programs that are in place across the region. You are invited to drop-in at your convenience to visit stalls and interactive displays and chat with staff. Information on the day will include:

• Overview of the Lower Vasse River Management Plan, including the sediment removal program
• Overview of the Toby Inlet Management Plan
• Mosquito management
• Waste education
• Possum protection
• And more!

Save the date: 2 November 2023, 3 – 6pm. In the Undalup Room, at the City of Busselton Administration Building (2 Southern Drive).
Registrations are not required, simply drop in!